Project title: Developing heparan sulfate glycan array This proposal is aimed at developing a high throughput method to study the interactions between heparan sulfate (HS) and proteins. HS is a highly sulfated polysaccharide displaying a wide range of biological functions. Glycan Therapeutics is a company specialized in HS related research products. In this proposal, an HS array technique will be constructed using both a microtiter plate format and a microarray format. The strength of the company is the capability of synthesizing structurally defined HS oligosaccharides using the chemoenzymatic method, allowing the synthesis of HS oligosaccharide in gram scale. This synthetic capability will ensure access to the oligosaccharide substrates at low cost and allows Glycan Therapeutics to have full control over the purity of the substrates. This unique strength will enable Glycan Therapeutics to produce high quality HS microtiter plates and HS micro-array chips at an affordable price. Aim 1 is designed to prepare HS microtiter plates based HS array. The major advantage of HS microtiter plate is that they are reusable and convenient. No additional equipment other than a microplate reader is needed. Furthermore, this method can be expanded to investigate the roles of HS in cell-based functional assays. Aim 2 is to prepare HS microarray technique. This technique will allow screening a very large number of HS oligosaccharides and proteins using very small amounts of carbohydrate and protein samples. The HS microarray technology will be readily integrated with existing carbohydrate-array methods in a centralized facility specialized in carbohydrate screening. In phase I studies, a library of 60 HS oligosaccharides will be affixed on a microtiter plate or on a microarray slide for biological screening. The HS microtiter plates or array slides will be tested thoroughly to ensure quality. In the phase II studies, the number of oligosaccharides on the microtiter plates and array slides will be expanded to 200 to fully represent the structures of HS isolated from natural sources. Success will lead to a convenient and reliable approach for improving research in glycosciences.